[Bump] Bump maccore to fix issues listing simulators on xcode12.

Commits:
i
* [mlaunch] Don't throw if the DVTAnalyticsKit is missing. (xamarin#2243) xamarin/maccore@5529194
* [mlaunch] Improve makefile to detect when the built app changes and re-install properly. xamarin/maccore@cd37e4d
* [mlaunch] Use SimDevice.LaunchApplicationAsync to launch applications like Xcode does. xamarin/maccore@1ad15ed
* [mlaunch] Launch watch apps directly in the watch simulator for watch iOS 7+. xamarin/maccore@e57ca5b
* [mlaunch] Fix makefile to work properly. (xamarin#2247) xamarin/maccore@af172cd
* [mlaunch] Automatically set NSUnbufferedIO in more cases to get text to stdout/stderr without delay. (xamarin#2246) xamarin/maccore@2d025ab
* [mlaunch] Disable any dock icons. (xamarin#2245) xamarin/maccore@e6eed65

Complete diff: xamarin/maccore@d425378...e6eed65]

mk/xamarin.mk

@@ -7,7 +7,7 @@ MONO_BRANCH    := $(shell cd $(MONO_PATH) 2> /dev/null && git symbolic-ref --sho
 endif
 
 ifdef ENABLE_XAMARIN
-NEEDED_MACCORE_VERSION := d4253786c02416dc6591f7420746c992ca100320
+NEEDED_MACCORE_VERSION := e6eed65b74728cab3093697711eb5ed4ffed772e
 NEEDED_MACCORE_BRANCH := xcode12
 
 MACCORE_DIRECTORY := maccore